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            "title": "Number of Recent Calls",
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            "content": "<p>You have a <code>RecentCounter</code> class which counts the number of recent requests within a certain time frame.</p>\n\n<p>Implement the <code>RecentCounter</code> class:</p>\n\n<ul>\n\t<li><code>RecentCounter()</code> Initializes the counter with zero recent requests.</li>\n\t<li><code>int ping(int t)</code> Adds a new request at time <code>t</code>, where <code>t</code> represents some time in milliseconds, and returns the number of requests that has happened in the past <code>3000</code> milliseconds (including the new request). Specifically, return the number of requests that have happened in the inclusive range <code>[t - 3000, t]</code>.</li>\n</ul>\n\n<p>It is <strong>guaranteed</strong> that every call to <code>ping</code> uses a strictly larger value of <code>t</code> than the previous call.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n[&quot;RecentCounter&quot;, &quot;ping&quot;, &quot;ping&quot;, &quot;ping&quot;, &quot;ping&quot;]\n[[], [1], [100], [3001], [3002]]\n<strong>Output</strong>\n[null, 1, 2, 3, 3]\n\n<strong>Explanation</strong>\nRecentCounter recentCounter = new RecentCounter();\nrecentCounter.ping(1);     // requests = [<u>1</u>], range is [-2999,1], return 1\nrecentCounter.ping(100);   // requests = [<u>1</u>, <u>100</u>], range is [-2900,100], return 2\nrecentCounter.ping(3001);  // requests = [<u>1</u>, <u>100</u>, <u>3001</u>], range is [1,3001], return 3\nrecentCounter.ping(3002);  // requests = [1, <u>100</u>, <u>3001</u>, <u>3002</u>], range is [2,3002], return 3\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= t &lt;= 10<sup>9</sup></code></li>\n\t<li>Each test case will call <code>ping</code> with <strong>strictly increasing</strong> values of <code>t</code>.</li>\n\t<li>At most <code>10<sup>4</sup></code> calls will be made to <code>ping</code>.</li>\n</ul>\n",
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            "exampleTestcases": "[\"RecentCounter\",\"ping\",\"ping\",\"ping\",\"ping\"]\n[[],[1],[100],[3001],[3002]]",
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                    "name": "Queue",
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                {
                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "class RecentCounter {\npublic:\n    RecentCounter() {\n        \n    }\n    \n    int ping(int t) {\n        \n    }\n};\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * RecentCounter* obj = new RecentCounter();\n * int param_1 = obj->ping(t);\n */",
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                    "lang": "Java",
                    "langSlug": "java",
                    "code": "class RecentCounter {\n\n    public RecentCounter() {\n        \n    }\n    \n    public int ping(int t) {\n        \n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * RecentCounter obj = new RecentCounter();\n * int param_1 = obj.ping(t);\n */",
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                    "lang": "Python",
                    "langSlug": "python",
                    "code": "class RecentCounter(object):\n\n    def __init__(self):\n        \n\n    def ping(self, t):\n        \"\"\"\n        :type t: int\n        :rtype: int\n        \"\"\"\n        \n\n\n# Your RecentCounter object will be instantiated and called as such:\n# obj = RecentCounter()\n# param_1 = obj.ping(t)",
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                {
                    "lang": "Python3",
                    "langSlug": "python3",
                    "code": "class RecentCounter:\n\n    def __init__(self):\n        \n\n    def ping(self, t: int) -> int:\n        \n\n\n# Your RecentCounter object will be instantiated and called as such:\n# obj = RecentCounter()\n# param_1 = obj.ping(t)",
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                    "lang": "C",
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                    "code": "\n\n\ntypedef struct {\n    \n} RecentCounter;\n\n\nRecentCounter* recentCounterCreate() {\n    \n}\n\nint recentCounterPing(RecentCounter* obj, int t) {\n  \n}\n\nvoid recentCounterFree(RecentCounter* obj) {\n    \n}\n\n/**\n * Your RecentCounter struct will be instantiated and called as such:\n * RecentCounter* obj = recentCounterCreate();\n * int param_1 = recentCounterPing(obj, t);\n \n * recentCounterFree(obj);\n*/",
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                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "public class RecentCounter {\n\n    public RecentCounter() {\n        \n    }\n    \n    public int Ping(int t) {\n        \n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * RecentCounter obj = new RecentCounter();\n * int param_1 = obj.Ping(t);\n */",
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                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "\nvar RecentCounter = function() {\n    \n};\n\n/** \n * @param {number} t\n * @return {number}\n */\nRecentCounter.prototype.ping = function(t) {\n    \n};\n\n/** \n * Your RecentCounter object will be instantiated and called as such:\n * var obj = new RecentCounter()\n * var param_1 = obj.ping(t)\n */",
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                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "class RecentCounter\n    def initialize()\n        \n    end\n\n\n=begin\n    :type t: Integer\n    :rtype: Integer\n=end\n    def ping(t)\n        \n    end\n\n\nend\n\n# Your RecentCounter object will be instantiated and called as such:\n# obj = RecentCounter.new()\n# param_1 = obj.ping(t)",
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                    "lang": "Swift",
                    "langSlug": "swift",
                    "code": "\nclass RecentCounter {\n\n    init() {\n        \n    }\n    \n    func ping(_ t: Int) -> Int {\n        \n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * let obj = RecentCounter()\n * let ret_1: Int = obj.ping(t)\n */",
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                    "lang": "Go",
                    "langSlug": "golang",
                    "code": "type RecentCounter struct {\n    \n}\n\n\nfunc Constructor() RecentCounter {\n    \n}\n\n\nfunc (this *RecentCounter) Ping(t int) int {\n    \n}\n\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * obj := Constructor();\n * param_1 := obj.Ping(t);\n */",
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                    "lang": "Scala",
                    "langSlug": "scala",
                    "code": "class RecentCounter() {\n\n    def ping(t: Int): Int = {\n        \n    }\n\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * var obj = new RecentCounter()\n * var param_1 = obj.ping(t)\n */",
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                    "lang": "Kotlin",
                    "langSlug": "kotlin",
                    "code": "class RecentCounter() {\n\n    fun ping(t: Int): Int {\n        \n    }\n\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * var obj = RecentCounter()\n * var param_1 = obj.ping(t)\n */",
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                {
                    "lang": "Rust",
                    "langSlug": "rust",
                    "code": "struct RecentCounter {\n\n}\n\n\n/** \n * `&self` means the method takes an immutable reference.\n * If you need a mutable reference, change it to `&mut self` instead.\n */\nimpl RecentCounter {\n\n    fn new() -> Self {\n        \n    }\n    \n    fn ping(&self, t: i32) -> i32 {\n        \n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * let obj = RecentCounter::new();\n * let ret_1: i32 = obj.ping(t);\n */",
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                {
                    "lang": "PHP",
                    "langSlug": "php",
                    "code": "class RecentCounter {\n    /**\n     */\n    function __construct() {\n        \n    }\n  \n    /**\n     * @param Integer $t\n     * @return Integer\n     */\n    function ping($t) {\n        \n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * $obj = RecentCounter();\n * $ret_1 = $obj->ping($t);\n */",
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                    "lang": "TypeScript",
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                    "code": "class RecentCounter {\n    constructor() {\n\n    }\n\n    ping(t: number): number {\n\n    }\n}\n\n/**\n * Your RecentCounter object will be instantiated and called as such:\n * var obj = new RecentCounter()\n * var param_1 = obj.ping(t)\n */",
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                    "lang": "Racket",
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                    "code": "(define recent-counter%\n  (class object%\n    (super-new)\n    (init-field)\n    \n    ; ping : exact-integer? -> exact-integer?\n    (define/public (ping t)\n\n      )))\n\n;; Your recent-counter% object will be instantiated and called as such:\n;; (define obj (new recent-counter%))\n;; (define param_1 (send obj ping t))",
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                    "lang": "Erlang",
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                    "code": "-spec recent_counter_init_() -> any().\nrecent_counter_init_() ->\n  .\n\n-spec recent_counter_ping(T :: integer()) -> integer().\nrecent_counter_ping(T) ->\n  .\n\n\n%% Your functions will be called as such:\n%% recent_counter_init_(),\n%% Param_1 = recent_counter_ping(T),\n\n%% recent_counter_init_ will be called before every test case, in which you can do some necessary initializations.",
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                    "lang": "Elixir",
                    "langSlug": "elixir",
                    "code": "defmodule RecentCounter do\n  @spec init_() :: any\n  def init_() do\n\n  end\n\n  @spec ping(t :: integer) :: integer\n  def ping(t) do\n\n  end\nend\n\n# Your functions will be called as such:\n# RecentCounter.init_()\n# param_1 = RecentCounter.ping(t)\n\n# RecentCounter.init_ will be called before every test case, in which you can do some necessary initializations.",
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